The Influence of Roentgen Rays, 

 Radioactive Substances, Light 

 and Electricity upon Metabolism 



THOMAS OEDWAY 



AXD 



ARTHUR KNUDSON 



ALBANY 



I. Roentgen Rays and Radioactive Substances 



Introduction. This discussion of the effect of Roentgen rays and 

 radioactive substances upon metabolism will be limited almost exclusively 

 to the more recent investigations upon man and other mammals. Xo at- 

 tempt will be made to duplicate the comprehensive surveys of previous au- 

 thors, nor can any detailed description of the physical nature of these forms 

 of energy be considered here. In studying the effects of radiations both ra- 

 dium and x-rays have been used as a means of experiment and the litera- 

 ture of both may be considered together. As a working basis for experiment 

 the effects of both are comparable especially in the case of the gamma rays 

 of radium. The effect of the other rays is not however to be considered 

 negligible but seems to differ in degree rather than in the kind of their 

 action so that the results do not conflict with our working hypothesis. 



In a survey of the subject of radiotherapy Ordway(a) (&) has briefly 

 described the methods of use of radioactive substances and Roentgen rays 

 for external or so-called surgical, and internal or medical conditions. He 

 has shown that our knowledge of the former is far greater than that of the 

 latter, which is to be advanced almost exclusively by a careful study of 

 the effect of these physical agents upon metabolism. 



Much of the earlier work has been rendered very uncertain because 

 of the faulty physical or biological methods. It is also unfortunate that 

 the application of the results has been in certain instances prema- 

 turely made to clinical therapeutic work on the assumption that any 

 changes in the metabolism were necessarily beneficial. 



Great caution should be used in estimating the therapeutic effect of 

 physical agents because of the marked fluctuations which occur in the 



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